A family consists of a domestic group of people (or a number of
domestic groups), typically affiliated by birth or marriage, or by analogous or
comparable relationships — including domestic partnership, cohabitation,
adoption, surname and (in some cases) ownership (as occurred in the Roman
Empire).

In many societies, family ties are only those recognized as such by law or a
similar normative system. Although many people (including social scientists)
have understood familial relationships in terms of "blood", many anthropologists
have argued that one must understand the notion of "blood" metaphorically, and
that many societies understand "family" through other concepts rather than
through genetic distance.

Article 16(3) of the Universal Declaration of Human Rights says: "The family
is the natural and fundamental group unit of society and is entitled to
protection by society and the State".

Definitions

A classic definition of family, according to anthropologist George Murdock,
is "a social group characterized by common residence, economic cooperation, and
reproduction. It includes adults of both sexes, at least two of whom maintain a
socially approved relationship, and one or more children, own or adopted, of the
sexually cohabiting adults."

The U.S. Bureau of the Census has defined a family as "two or more persons
related by birth, marriage, or adoption, who reside together." Thus a family can
be two or more adult siblings living together, a parent and child or children,
two adults who are related by marriage but have no children, or adults who adopt
a child.

The Merriam-Webster definition of "family" is:

the basic unit in society traditionally consisting of two parents rearing
their children; also : any of various social units differing from but regarded
as equivalent to the traditional family <a single-parent family>

Family in the West

Family arrangements in the United States have become more diverse with no
particular household arrangement representing half of the United States
population.

The different types of families occur in a wide variety of settings, and
their specific functions and meanings depend largely on their relationship to
other social institutions. Sociologists have an especial interest in the
function and status of these forms in stratified (especially capitalist)
societies.

Non-scholars, especially in the United States and Europe, use the term
"nuclear family" to refer to conjugal families. Sociologists distinguish between
conjugal families (relatively independent of the kindreds of the parents and of
other families in general) and nuclear families (which maintain relatively close
ties with their kindreds).

Non-scholars, especially in the United States and Europe, also use the term
"extended family". This term has two distinct meanings. First, it serves as a
synonym of "consanguinal family". Second, in societies dominated by the conjugal
family, it refers to kindred (an egocentric network of relatives that
extends beyond the domestic group) who do not belong to the conjugal family.

These types refer to ideal or normative structures found in particular
societies. Any society will exhibit some variation in the actual composition and
conception of families. Much sociological, historical and anthropological
research dedicates itself to the understanding of this variation, and of changes
in the family form over time. Thus, some speak of the bourgeois family, a
family structure arising out of 16th-century and 17th-century European
households, in which the family centers on a marriage between a man and woman,
with strictly-defined gender-roles. The man typically has responsibility for
income and support, the woman for home and family matters.

Philosophers and psychiatrists like Deleuze, Guattari, Laing, Reich,
explained that the patriarchal-family conceived in the West tradition
(husband-wife-children) serves the purpose of perpetuating a propertarian and
authoritarian society. The child grows according to the Oedipal model typical of
capitalist societies and he becomes in turn owner of submissive children and
protector of the woman.

According to the analisys of Michel Foucault, in the west:

the [conjugal] family organization, precisely to the extent that it was
insular and heteromorphous with respect to the other power mechanisms, was
used to support the great "maneuvers" employed for the Malthusian control of
the birthrate, for the populationist incitements, for the medicalization of
sex and the psychiatrization of its nongenital forms.

In contemporary Europe and the United States, people in academic, political
and civil sectors have called attention to single-father-headed households, and
families headed by same-sex couples, although academics point out that these
forms exist in other societies. Also the term blended family or stepfamily
describes families with mixed parents: one or both parents remarried, bringing
children of the former family into the new family.

Economic function of the family

Anthropologists have often supposed that the family in a traditional society
forms the primary economic unit. This economic role has gradually diminished in
modern times, and in societies like the United States it has become much smaller
— except in certain sectors such as agriculture and in a few upper class
families. In China the family as an economic unit still plays a strong role in
the countryside. However, the relations between the economic role of the family,
its socio-economic mode of production and cultural values remain highly complex.

Extended middle-class Midwestern U.S. family of Danish/German extraction

Families and political structure

On the other hand family structures or its internal relationships may affect
both state and religious institutions. J.F. del Giorgio in The Oldest
Europeans points that the high status of women among the descendants of the
post-glacial Paleolithic European population was coherent with the fierce love
of freedom of pre-Indo-European tribes. He believes that the extraordinary
respect for women in those families made that children raised in such atmosphere
tended to distrust strong, authoritarian leaders. According to del Giorgio,
European democracies have their roots in those ancient ancestors.

Kinship terminology

Anthropologist Lewis Henry Morgan (1818–1881) performed the first survey of
kinship terminologies in use around the world. Though much of his work is now
considered dated, he argued that kinship terminologies reflect different sets of
distinctions. For example, most kinship terminologies distinguish between sexes
(the difference between a brother and a sister) and between generations (the
difference between a child and a parent). Moreover, he argued, kinship
terminologies distinguish between relatives by blood and marriage (although
recently some anthropologists have argued that many societies define kinship in
terms other than "blood").

However, Morgan also observed that different languages (and thus, societies)
organize these distinctions differently. He thus proposed to describe kin terms
and terminologies as either descriptive or classificatory. "Descriptive" terms
refer to only one type of relationship, while "classificatory" terms refer to
many types of relationships. Most kinship terminologies include both descriptive
and classificatory terms. For example, Western societies provide only one way to
express relationship with one's brother (brother = parents' son); thus, in
Western society, the word "brother" functions as a descriptive term. But many
different ways exist to express relationship with one's male first-cousin
(cousin = mother's brother's son, mother's sister's son, father's brother's son,
father's sister's son, and so on); thus, in Western society, the word "cousin"
operates as a classificatory term.

Morgan discovered that a descriptive term in one society can become a
classificatory term in another society. For example, in some societies one would
refer to many different people as "mother" (the woman who gave birth to oneself,
as well as her sister and husband's sister, and also one's father's sister).
Moreover, some societies do not lump together relatives that the West classifies
together. For example, some languages have no one word equivalent to "cousin",
because different terms refer to mother's sister's children and to father's
sister's children.

Armed with these different terms, Morgan identified six basic patterns of
kinship terminologies:

Hawaiian: the most classificatory; only distinguishes between sex and
generation.

Sudanese: the most descriptive; no two relatives share the same term.

Eskimo: has both classificatory and descriptive terms; in addition to sex
and generation, also distinguishes between lineal relatives (those related
directly by a line of descent) and collateral relatives (those related by
blood, but not directly in the line of descent). Lineal relatives have highly
descriptive terms, collateral relatives have highly classificatory terms.

Iroquois: has both classificatory and descriptive terms; in addition to
sex and generation, also distinguishes between siblings of opposite sexes in
the parental generation. Siblings of the same sex class as blood relatives,
but siblings of the opposite sex count as relatives by marriage. Thus, one
calls one's mother's sister "mother", and one's father's brother "father";
however, one refers to one's mother's brother as "father-in-law", and to one's
father's sister as "mother-in-law".

Crow: like Iroquois, but further distinguishes between mother's side and
father's side. Relatives on the mother's side of the family have more
descriptive terms, and relatives on the father's side have more classificatory
terms.

Omaha: like Iroquois, but further distinguishes between mother's side and
father's side. Relatives on the mother's side of the family have more
classificatory terms, and relatives on the father's side have more descriptive
terms.

Western kinship

The relationships and names of various family members in the English
language.

Most Western societies employ Eskimo kinship terminology. This kinship
terminology commonly occurs in societies based on conjugal (or nuclear)
families, where nuclear families have a degree of relatively mobility.

Members of the nuclear family use descriptive kinship terms:

Mother: the female parent

Father: the male parent

Son: the males born of the mother; sired by the father

Daughter: the females born of the mother; sired by the father

Brother: a male born of the same mother; sired by the same father

Sister: a female born of the same mother; sired by the same father

Such systems generally assume that the mother's husband has also served as
the biological father. In some families, a woman may have children with more
than one man or a man may have children with more than one woman. The system
refers to a child who shares only one parent with another child as a
"half-brother" or "half-sister". For children who do not share biological or
adoptive parents in common, English-speakers use the term "step-brother" or
"step-sister" to refer to their new relationship with each other when one of
their biological parents marries one of the other child's biological parents.

Any person (other than the biological parent of a child) who marries the
parent of that child becomes the "step-parent" of the child, either the
"stepmother" or "stepfather". The same terms generally apply to children adopted
into a family as to children born into the family.

Typically, societies with conjugal families also favor neolocal residence;
thus upon marriage a person separates from the nuclear family of their childhood
(family of orientation) and forms a new nuclear family (family of procreation).
This practice means that members of one's own nuclear family once functioned as
members of another nuclear family, or may one day become members of another
nuclear family.

Members of the nuclear families of members of one's own (former) nuclear
family may class as lineal or as collateral. Kin who regard them as lineal refer
to them in terms that build on the terms used within the nuclear family:

Grandparent

Grandfather: a parent's father

Grandmother: a parent's mother

Grandson: a child's son

Granddaughter: a child's daughter

For collateral relatives, more classificatory terms come into play, terms
that do not build on the terms used within the nuclear family:

When additional generations intervene (in other words, when one's collateral
relatives belong to the same generation as one's grandparents or grandchildren),
the prefix "grand" modifies these terms. (Although in casual usage in the USA a
"grand aunt" is often referred to as a "great aunt", for instance.) And as with
grandparents and grandchildren, as more generations intervene the prefix becomes
"great grand", adding an additional "great" for each additional generation.

Most collateral relatives have never had membership of the nuclear family of
the members of one's own nuclear family.

Cousin: the most classificatory term; the children of aunts or
uncles. One can further distinguish cousins by degrees of collaterality and by
generation. Two persons of the same generation who share a grandparent count
as "first cousins" (one degree of collaterality); if they share a
great-grandparent they count as "second cousins" (two degrees of collaterality)
and so on. If two persons share an ancestor, one as a grandchild and the other
as a great-grandchild of that individual, then the two descendants class as
"first cousins once removed" (removed by one generation); if the shared
ancestor figures as the grandparent of one individual and the
great-great-grandparent of the other, the individuals class as "first cousins
twice removed" (removed by two generations), and so on. Similarly, if the
shared ancestor figures as the great-grandparent of one person and the
great-great-grandparent of the other, the individuals class as "second cousins
once removed". Hence the phrase "third cousin once removed upwards".

Distant cousins of an older generation (in other words, one's parents' first
cousins), though technically first cousins once removed, often get classified
with "aunts" and "uncles".

Similarly, a person may refer to close friends of one's parents as "aunt" or
"uncle", or may refer to close friends as "brother" or "sister", using the
practice of fictive kinship.

English-speakers mark relationships by marriage (except for wife/husband)
with the tag "-in-law". The mother and father of one's spouse become one's
mother-in-law and father-in-law; the female spouse of one's child becomes one's
daughter-in-law and the male spouse of one's child becomes one's son-in-law. The
term "sister-in-law" refers to three essentially different relationships, either
the wife of one's brother, or the sister of one's spouse, or the wife of one's
spouse's sibling. "Brother-in-law" expresses a similar ambiguity. No special
terms exist for the rest of one's spouse's family.

The terms "half-brother" and "half-sister" indicate siblings who one share
only one biological or adoptive parent.

Contemporary perception

Contemporary society generally views family as a haven from the world
supplying absolute fulfilment. The family as a haven encouraging “intimacy, love
and trust where individuals may escape the competition of dehumanising forces in
modern society” The family is often referred to as a haven providing love and
protection from the rough and tumble industrialised world, and as a place where
warmth, tenderness and understanding can be expected from a loving mother and
protection from the world can be expected from the father. However, the idea of
protection is declining as civil society faces less internal conflict combined
with increased civil rights and protection from the state. To many, the ideal of
personal or family fulfilment has replaced protection as the major role of the
family. The family now supplies what is “vitally needed but missing from other
social arrangements”.

Social conservatives often express concern over a purported decay of the
family and see this as a sign of the crumbling of contemporary society. They
feel that the family structures of the past were superior to those today and
believe that families were more stable and happier at a time when they did not
have to contend with problems such as illegitimate children and divorce. Others
refute this theory, claiming “there is no golden age of the family gleaming at
us in the far back historical past”.